Sewing-machine.



M. HEMLEB. SEWING MACHINE. APPLIOATION I'ILED OUT. 30, 1909.

wgfmsn WITNESSES Patented June 15, 1909.-

To all whom it may mam.-

UNITED STATES PATENT OFFICE.

MARTIN HEMLEB, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE MANUFACTUB ING COMPANY, A CORPORATION OF NEW JERSEY,

SEWING-MACHINE.

Specification of Letters Patent.

Patented Tune 15, 1999.

-=A'pplication filed p wter a0, 1908. Serial 110460.199.

Be it known that I; MARTIN HEMLnB, a

citizen of the United States, residing at Elizabeth, in the countyof; Union and State of New Jersey, have invented certain new and, useful ilmprovementsfiin Sewing-Maof which the following is a specification, reference being had therein to the accomv panying drawings.

This invention has for its ob'ect to provide a simple and effective stitchorming mech anism for producing a double chain-stitch in connection more particularly with machines for stitching gloves of silk or other woven material.

As herein represented, the present invention is embodied ,in a machine of the general style of the well-known Singer No. 24 machine, in which the main-shaft is journaled within the base beneath the work-plate and is provided at its rearward end with a crank having. a pitman connection with a lateral crankarm of the needle-actuating rock-shaft journaled in the overhanging bracket-arm and having a driving relation with the forward end of the needle afforded by'a crank- .anditman connection with the needle bar.

The ooper is mounted rigidly upon the forward end of a supporting rock-shaft j ournaled in the bed beneath themain-shaft and havin an upwardly extending yoke whose space parallel members engage upon opposite'sides two adjacently arranged cams of equal throw with concentric outer and inner portions of different lengths, the angular eX- tent of the concentric outer portion of one cam corresponding with that of the miner vconcentric portion of the other cam. Aree,

.eji'procating spreader is provided :to engage the looper-thread above the looper 'and'carry it crosswise of the looper path in spreading it forthe subsequent descent of the needle.

'Bythe particular form of looper actuating cams Y abs-spa centric portion ofjthe wider cam disposed in the direction .ot'rnovement of the looper in seizing'jthe' nejcdle thread 100 s, the looper is fg' a needle-thread loop, 1n order I 7 reader may havetime to seize the looper ad and spread the same for the subsequen descent of the needle, while the retrograde 't the looper and its advance g needleethreaddoop seizure i; i p dl-y and with but slight .bodying work-p arm removed to expose the parts covered escribed, with the outer con- -l. ing --,dwell in its a Vance-position dwell in. the reversal of its to-and-fro movements. It has been found that, with the de' scribed'.form of open cam mechanism for the looper actuation, the crank-anditman con- 'nections intermediate the main-s aft andthe needle-bar provide a suitable timing for proper cooperation of. the needle with the lower thread handling mechanism.

The present invention includes, certain other-features which will be hereinafter described and pointed out in the appendedclaims.

,In the accompanying drawings, Figure 1 is aperspective view of a sewinglmachine emthe present'improvements, with the ate and the face-plate of the bracketthereby, and Fig. '2 1s 'a similar .view, from a different position, of the operative parts beneath the work-plate. Fig. 3 is a perspective .view of the looper-carrierandlooper with the latter shifted from normal ositi'on for threading. Fig. 4 is a detail slde elevation showing the looper-actuating cam and the.

yoke embracing the same with their supporting shafts. The machine base-plate 1 and overhangingbracket-arm 2,

in the head 3.01. which ismounted the ver-' tically reciprocating needle-bar '41 carrying the eye-pointed nieedle 5 and provided inter mediate its bearings with' the fixed collar '6 connected by means of the fitman 7 with a frame comprises the usual.

crank-pin 8 carriedupon the forward end of the needle-actuating rock-shaft 9 journaled' .in the bracket-arm and havingvat it rearward end a crank-arm 10' connected by; means ofthe pitman 11 with the crank 12 iii the rearward end of the main-shaft 13 flour-- naled in the base 1 beneath the work-plate 1.41 in a manner well-known. 'Rigidly secured to the pitman 7 b means of the fastening screw '15,is a lateral y extending take-u 'arm 16 having at its outer end the nsua thread: eye and working in a vertical slot-17 in-the front side of the head 3 of the bracket-arm.

Journaled also in the head 3 is the usual presser-bar 18' carrying the presser-foot l9 and normally depressed by means of the spring 20 interposed between the upper bearing and the thrust-block 21 adaptedforenga ement by the lifting lever 22.

eneath the main-shaft 13 and paralleltherewith is journaled the looper-su portin shaft 23 provided at its outer end wit a bloc 2-1 having the projecting cars between which is pivoted by means of the pin 26 the shank 27 of the looper whose blade 28 is provided with the usual thread-eyes 2S in the point and heel and intermediategroove or channel for the lower thread. Beneath the looper blade 28 and extending forwardly somewhat beyond the same ,is a needle-guard finger 29, integral wit-h the shank 2'7 and blade 28, whose upper edge is beveled forwardly and merges into the fiat front face which lies substantially in the plane of the slightly offset point of the looper, as represented in Figs. 1 and 2. This needle-guard finger is provided to insure the glancing off of the needle in case it should be deflected in penetrating the work, thus insuring against collision with the advancing pointrof the looper in the seizure of the needle-thread loop. To the looper shank is scoured by means of the screw 30 the foot 31 of a threadguide formed with the open eyes 32 and 33 to receive the thread passing from the source of supply to t-he'thread eyes in the looper. The block 24 is provided at the upper end with the spaced guide-lugs 34 between which the looper shank is locked by means of the angular latch-lever 35 pivoted within a slot in said block bymeans of a. pin 36 and having interposed between its tail 37 and the inner end of said slot a spring 38 by means of which the lat-ch is normally closed.

Upon the rearward portion of the loopersupporting shaft 23 is fixed the upwardly extending yoke 39 having the. spaced parallel wearing members 40 and 41 embracing the two-part cam formed of the sections 42 and 43 fixed upon the main-shaft 13. As will be observed by reference to Fig. 4, both cam sections are of the general pattern known as triangular having their concentric inner and outer portions of the same height and curvature but of different extent, the length of the outer concentric portion of the wider cam 42 being of the same angular extent as the inner concentric portion of the narrower cam sectic 43. in other words, while differing in actual length, the angular extent of the concentric portion of greater curvature of the cam 42 corresponds with the angular extent ofthe concentric portion of smaller curvature (t. 6., that nearest the axis of the shaft 13) of the cam 43. This is true because while the member 40 of the yoke 39 is in contact witli the outer concentric portion of the cam 12, or that having the greatt-zsr radius, the yoke member 11 remains in contact with the inner concentric portion. or that having least radius, of the cam 43. so that the space between the yoke members 4 and 41 will be completely occupied (,lttl'lllfi' the dwell of the cam in order to prevent lost motion and consequent uncertainty of control of the looper rock-shaft To distend the looper-tl'iread between the eye of the looper and the under side of the material for passage of the, needle, a notched spreading finger 44 is secured by means of a screw 45 upon the forward end of an angular lever 46 fulcrumed upon the frame of the machine by means of the screw 47 and provided intermediate the fulcrum and the spreader-finger with a roller-stud 48 entering a cam-groove 49 in a cam-cylinder 50 fixed jecting arm of the feed-rocker actuate by a connection with the feed-actuating eccentrio 61 upon the rearward portion of the mam-shaftand provided with lifting means upon the forward end of the main-shaft as inthe Singer machine before referred to.

In threading the machine, the thread is taken from a spool upon the forward end of the spool-pin 62 carried by the standard 63 which is mounted upon the bracket-arm, being led through the tension device 64, thence through a fixed guide-eye 65 upon the arm 2, to the eye of the take-up arm 16, from which it is led through a guide-eyefiti upon the upper end of the needle-bar downwardly to the eye of the needle 5. The looper-thread is led from a spool upon the rearward end of the spool-pin 62 to the tension device 67, and thence under the guide-loop 53 over the take-up pin 55 and under the guide-loop 54 through the guide-eyes 32 and to the thread channel of the looper.

In the operation of the machine, the needle descends and upon beginning its upward movement throws out its loop which is entered by the quick advance of the looper which pauses at its advance position to permit the en 'agement of its own thread by the spreader, which latter carries a bight of looper thread transversely beyond the needle path after which the needle descends through the looper-thread bight and the looper recedes to shed the previously seized needlethread loop, returning to initial retracted position. As the looper-thread take-up finger 55 is carried by the looper rock-shaft, it will be observ ed that it acts to'pull up the looper-thread only while the looper is receding from advance to initial retracted position, and that itgives up the looper-thread as the looper advances to seize a succeeding needle-tl'nead loop. I

It will be observed that the two-part looper-actuating cam above described afiords a cam of the fopen type, although positively acting at all'times, and thus permits any dirt which may be introduced therein in the operation of the machine to become dislodged and to drop out of the same so that such cam and its follower are at all times clean and free from grit and foreign matter which would impair durability. It will also be observed, that the form of cam herein shown and described is such that the wearing faces ofboth cam sections and follower may be extended lengthwise of the main-shaft to any required degree so as to secure the requisite wearing surface and insure the greatest I durability of the parts; while the shape of the sections is such as to provide easy movements for the looper rock-shaft although affording the requisite dwell of the looper in its advance position for the necessary cooperation of the spreader and the needle, which latter is thus-enabled to' be driven by the simple cranleaiirl-pitinan connections before described so as to produce a light running and noiseless machine of high speed capacity.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, the combination with the frame comprising a base and an overhanging bracket-arm, and a main-shaft j ournaled in the base, of a reciprocating needle, a needle-actuating rock-shaft mounted upon the bracket-arm parallel with the mainshaft, crank-and-pitman connections intermediate one end of the needle-actuating rock-shaft and the main-shaft and between the other end of said rock-shaft and the nee dle, a looper rock-shaft j ournaled in the base beneath and parallel with-the main-shaft, a looper fixed upon said looper rock-shaft, a two-part cam fixed upon the main-shaft and composed of adjacent sections each of triangular form with concentric outer and inner portions of equal height but of different lengths, and with the angular extent of the outer concentric portion of one cam-section corresponding with that of the inner concentric portion of the other cam section,-and a yoke fixed upon the looper shaft and having spaced parallel members adapted toengage the respective cams upon opposite sides of the main-shaft.

2. In a sewing machine, the combination with the frame comprising a base and an overhanging bracket-arm, and a main-shaft j ournaledin the base, of a. reciprocating needle, a needle-actuating rock-shaftmounted upon the bracket-arm parallel with the mainshaft, crank-zind-pitman connections intermediate one end of the needle-actuating rock-shaft and the main-shaft and between the other end of said rock-shaft and the needle, a looper rock-shaft journaled in the base beneath and parallel with the main-shaft, an

eyed thread-carrying looper fixed upon said looperrock-shaft, a two-part cam fixed upon the main-shaft and composed of adjacent sections each of triangular form with concentric outer and inner portions of equal height but of diflerent lengths, and with the angular extent of the outer concentric portion of one cam section corresponding with that of the inner concentric portion of the other cam section, a yoke fixed upon the looper-shaft and having spaced parallel members adapted to-engage the respective cams upon opposite sides of the main-shaft, a spreader movable transversely of the looper path above the eye of the looper in its advance position, and means upon the main-shaft for reciprocating said spreader.

3. In a sewing machine, the combination with the frame comprising a base and an overhanging bracket-arm, and a main-shaft journaled in the base, of a reciprocating needle, an operative connection intermediate 'said needle and the main-shaft, a looper rockshaft and movable intermediate said thread- 1 eyes synchronously with'the operative movements of the looper.

4. In a sewing machine, the combination with the frame comprising a base and an overhanging bracket-arm, anda main-shaft journaled in the base, of a reciprocating needle, an operative connection intermedlate said needle and the main-shaft, a looper rockshaft journaled in the base beneath and par-' allel with the main-shaft, a looper carrying block fixed upon said rock-shaft, a looper having'its shank pivotally mounted in said block and provided with an integral eyed loop+seizing blade and a beveled needleguard finger disposed beneath the'same and having its operative face in substantially the planeof the point of the looper-blade, a spring-pressed latch upon the looper-carrying block adapted to normally engage the looper-shank and retain the same in opera tive position upon said block, a looper-actuating cam fixed upon the main-shaft, and 'a yoke fixed upon the looper-shaft and em bracing said actuating cam.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

. MARTIN HEMLEB.

Witnesses:

HENRY J. MILLER, JosEPH F, JAQUITH. 

